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heterometallic Mg-Ni-Mg Complex Promoted hydrosilylation of Alkenes: Catalytic Performance and Intermediates Characterization

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Chinese Journal of Chemistry 2024年第18期42卷 2133-2139页

作者： Yanping Cai Shengjie Jiang Xin xu Key Laboratory of Organic Synthesis of Jiangsu Province College of ChemistryChemical Engineering and Materials ScienceSoochowUniversitySuzhouJiangsu215123China

background and Originality Content The catalytic hydrosilylation of unsaturated hydrocarbons,facilitated by transition metal(TM),is widely recognized as a proficient technique for the synthesis of high-value organosilicon compounds'ti-4l over the past few decades,the most dominant *** in hydrosilylation processes have been constituted by pre-Ccious metar complexesroceinerecent vears omore sustainabile earth-abundant metal catalysts have received increased attentionj2-14l The classcal mechanism of transition metal-catalyzed hydrosilylation is generally accomplished through a series of fundamental processes(Scheme 1a),including(i)coordination and oxidative addition of Si-h.b.nd to a low-valent metal center to form e.g.,o-complex or silyl metal hydride;(ii)insertion of.C-C multipe bonds intometal-hdridelsior metal-silicon bond;jiol and(ii)reductive elimination that forwards the hydrosilylated product with Markovnikov or anti-Markovnikov selectivity.

关键词： heterometallic complex Cooperative effect hydrosilylation Magnesium Nickel hydride

ZnO Additive boosts Charging Speed and Cycling Stability of Electrolytic Zn–Mn batteries

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Nano-Micro Letters 2024年第4期16卷 293-304页

作者： Jin Wu Yang Tang haohang xu Guandie Ma Jinhong Jiang Changpeng Xian Maowen xu Shu‑Juan bao hao Chen Institute for Clean Energy&Advanced Materials School of Materials and EnergySouthwest UniversityChongqing 400715People’s Republic of China

Electrolytic aqueous zinc-manganese(Zn–Mn) batteries have the advantage of high discharge voltage and high capacity due to two-electron reactions. however, the pitfall of electrolytic Zn–Mn batteries is the sluggish deposition reaction kinetics of manganese oxide during the charge process and short cycle life. We show that, incorporating ZnO electrolyte additive can form a neutral and highly viscous gel-like electrolyte and render a new form of electrolytic Zn–Mn batteries with significantly improved charging capabilities. Specifically, the ZnO gel-like electrolyte activates the zinc sulfate hydroxide hydrate assisted Mn^(2+) deposition reaction and induces phase and structure change of the deposited manganese oxide(Zn_(2)Mn_(3)O_8·h_(2)O nanorods array), resulting in a significant enhancement of the charge capability and discharge efficiency. The charge capacity increases to 2.5 mAh cm^(-2) after 1 h constant-voltage charging at 2.0 V vs. Zn/Zn^(2+), and the capacity can retain for up to 2000 cycles with negligible attenuation. This research lays the foundation for the advancement of electrolytic Zn–Mn batteries with enhanced charging capability.

关键词： Electrolytic aqueous zinc-manganese batteries Electrolyte ph value ZnO electrolyte additive Fast constant-voltage charging ability

LÉVY AREA ANALYSIS AND PARAMETER ESTIMATION FOR FOU PROCESSES VIA NON-GEOMETRIC ROUGh PATh ThEORY

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Acta Mathematica Scientia 2024年第5期44卷 1609-1638页

作者： Zhongmin QIAN Xingcheng xu Mathematical Institute University of OxfordOxfordOX26GGUK Shanghai Artificial Intelligence Laboratory Shanghai200232China School of Mathematical Sciences Peking UniversityBeijing100871China

This paper addresses the estimation problem of an unknown drift parameter matrix for a fractional Ornstein-Uhlenbeck process in a multi-dimensional *** tackle this problem,we propose a novel approach.b.sed on rough path theory that allows us to construct pathwise rough path estimators from both continuous and discrete observations of a single *** approach is particularly suitable for high-frequency *** formulate the parameter estimators,we introduce a theory of pathwise Itôintegrals with respect to fractional brownian *** establishing the regularity of fractional Ornstein-Uhlenbeck processes and analyzing the long-term behavior of the associated Lévy area processes,we demonstrate that our estimators are strongly consistent and pathwise *** findings offer a new perspective on estimating the drift parameter matrix for fractional Ornstein-Uhlenbeck processes in multi-dimensional settings,and may have practical implications for fields including finance,economics,and engineering.

关键词： Itôintegration Lévy area non-geometric rough path fOU processes pathwise stability long time asymptotic high-frequency data

2D Ca/Nb-based perovskite oxide with Ta doping as highly efficient h_(2)O_(2)synthesis catalyst

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Nano Research 2024年第6期17卷 4934-4942页

作者： Xingchen Yang Yang Gao Xiaohui xu Wenqiang xu Denghui Wang bin Luo Dong Liu Tao Liang bin Wang CAS Key Laboratory of Nanosystem and hierarchical Fabrication National Center for Nanoscience and TechnologyBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Nanomaterials Centre School of Chemical Engineering and Australian Institute for Bioengineering and Nanotechnologythe University of QueenslandSt LuciaQLD 4072Australia State Key Laboratory of Organic–Inorganic Composites College of Chemical EngineeringCollege of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China hangzhou Institute for Advanced Study University of Chinese Academy of SciencesHangzhou 310024China State Key Lab of Silicon Materials Zhejiang UniversityHangzhou 310027China

Perovskite oxides(POs)are emerging as a class of highly efficient catalysts for reducing oxygen to h_(2)*** a rich variety of POs-based catalysts have been developed by tuning the complex composition,a highly efficient PO catalyst that is able to alter the reaction pathway from a 4e−process to a 2e−process for h_(2)O_(2)production has rarely been *** modified the structure and composition of a Ca-and Nb-based PO material by realizing a uniform two-dimensional(2D)morphology and varied Ta doping,resulting in the 2D Ca_(2)Nb_(3−x)Ta_(x)O_(10)−(x=0,0.5,1,and 1.5)monolayer *** obtained catalysts exh.b.t a dominant 2e−pathway and show exceptional h_(2)O_(2)production *** typical Ca_(2)Nb_(2.5)Ta_(0.5)O_(10)−nanoflakes showed an onset potential of 0.735 V *** hydrogen electrode(RhE),a remarkably high selectivity over 95%across a wide range of 0.3-0.7 V,an impressively high Faradaic efficiency of 94%,and a notable h_(2)O_(2)productivity of 1571 mmol·gcat^(−1)·h^(−1).These findings highlight the great potential of 2D perovskite oxide nanoflakes as advanced electrocatalysts for 2e−oxygen reduction reaction.

关键词： perovskite oxide h_(2)O_(2) two-electron oxygen reduction reaction catalyst Ca_(2)Nb_(3-x)Ta_(x)O_(10)-nanoflakes

Gravitational wave footprints from higgs-portal scalegenesis with multiple dark chiral scalars

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Chinese Physics C 2024年第4期48卷 209-221页

作者： he-xu Zhang Shinya Matsuzaki hiroyuki Ishida Center for Theoretical Physics and College of Physics Jilin UniversityChangchun 130012China Center for Liberal Arts and Sciences Toyama Prefectural UniversityToyama 939-0398Japan

We discuss the gravitational wave(GW)spectra predicted from the electroweak scalegenesis of the higgs portal type with a large number of dark chiral flavors,which many flavor QCD would underlie and give the dynamical explanation of the negative higgs portal coupling required to trigger the electroweak symmetry *** employ the linear-sigma model as the low-energy description of dark many flavor QCD and show that the model undergoes ultra-supercooling due to the produced strong first-order thermal phase transition along the(approximately realized)flat direction based on the Gildener-Weinberg *** through evaluation of the bubble nucleation/percolation,we address the reheating and relaxation processes,which are generically non-thermal and *** the reheating epoch in terms of the e-folding number,we propose proper formulae for the redshift effects on the GW frequencies and signal *** then turns out that the ultra-supercooling predicted from the higgs-portal scalegenesis generically yields none of GW signals with the frequencies as low as nano hz,unless the released latent heat is transported into another sector other than reheating the ***,models of this class prefer to give the higher frequency signals and still keeps the future prospected detection sensitivity,like at LISA,bbO,and DECIGO,*** also find that with large flavors in the dark sector,the GW signals are made further smaller and the peak frequencies *** phenomenological consequences related to the multiple chiral scalars include the prediction of dark pions with the mass much less than TeV scale,which is also briefly addressed.

关键词： gravitational wave electroweak scalegenesis many flavor QCD

Multifunctional RGD coated a single-atom iron nanozyme:A highly selective approach to inducing ferroptosis and enhancing immunotherapy for pancreatic cancer

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Nano Research 2024年第6期17卷 5469-5478页

作者： haoqi Pan xu Chen Mingming Xiao he xu Jiansheng Guo Zhiyi Lu Dong Cen Xianjun Yu Si Shi Department of Pancreatic Surgery Fudan University Shanghai Cancer CenterShanghai 200032China Department of Oncology Shanghai Medical CollegeFudan UniversityShanghai 200032China Shanghai Pancreatic Cancer Institute Shanghai 200032China Pancreatic Cancer Institute Fudan UniversityShanghai 200032China Key Laboratory of Advanced Fuel Cells and Electrolyzers Technology of Zhejiang Province Qianwan Institute of CNITECHNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Department of Pathology of Sir Run Run Shaw hospital Zhejiang University School of MedicineHangzhou 310016China Key Laboratory of Laparoscopic Technology of Zhejiang Province Department of General SurgerySir Run Run Shaw HospitalZhejiang University School of MedicineHangzhou 310016China

Nanozyme is a new promising approach to cancer therapy for its ability to induce ferroptosis by activating h_(2)O_(2)via a traditional radical pathway and enhance cancer ***,short half-life period of hydroxyl radical(·Oh)results in unsatisfied ***,we synthesized a single-atom iron nanozyme(Fe-SAzyme),which can activate h_(2)O_(2)via a non-radical pathway to generate Fe-based reactive oxygen species(ROS)(O=FeO_(3)=O)for promoting the ferroptosis of pancreatic cancer *** Fe-SAzyme could be specifically phagocytosed by pancreatic cancer cells,increasing ROS levels and inh.b.ting glutathione(GSh)synthesis,which activates *** magnetic resonance imaging(MRI)showed decreased T2 signal after intravenous injection of RGD@Fe-AC(AC=activated carbon).Moreover,RGD@Fe-AC promoted dendritic cell(DC)maturation,overcame Treg-mediated immunosuppression,activated T cells to trigger adaptive immune responses,and enhanced the efficacy ofα-PD-L1 *** research demonstrated that RGD@Fe-AC provided a straightforward,easily implemented,and selective approach for pancreatic cancer treatment and immunotherapy.

关键词： single-atom iron nanozyme pancreatic cancer immunotherapy ferroptosis

Amino acids modified nanoscale zero-valent iron:Density functional theory calculations,experimental synthesis and application in the Fenton-like degradation of organic solvents

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Journal of Environmental Sciences 2024年第1期135卷 296-309页

作者： Xingchen Yang Fucheng Ming Jianlong Wang Lejin xu Department of Nuclear Engineering and Technology School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China China-EU Institute for Clean and Renewable Energy Huazhong University of Science and TechnologyWuhan 430074China Institute of Nuclear and New Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of EducationTsinghua UniversityBeijing 100084China beijing Key Laboratory of Radioactive Wastes Treatment Tsinghua UniversityBeijing 100084China

To improve the adsorption and catalytic performance of heterogeneous Fenton-like catalysts for oil wastes,amino acids were used to modify nanoscale zero-valent iron(AA@Fe^(0)),which were applied in the Fenton-like degradation of organic solvents(tributyl phosphate and n-dodecane,named TbP and DD).Twelve amino acids,i.e.,glycine(Gly),alanine(Ala),leucine(Leu),proline(Pro),phenylalanine(Phe),methionine(Met),cysteine(Cys),asparagine(Asn),serine(Ser),glutamic acid(Glu),lysine(Lys)and arginine(Arg),were selected and calculated by density functional theory(DFT).The optimized structure,charge distribution,the highest occupied molecular orbital(hOMO),the lowest unoccupied molecular orbital(LUMO),interaction region indicator(IRI)isosurface map and adsorption energy of AA@Fe^(0),AA@Fe^(0)-TbP and AA@Fe^(0)-DD were studied,which indicated that Fe is more likely to approach and charge transfer with-COO and-Nh_(3) on theα-carbon of amino *** is strong attraction between Fe and–COO,and Van der Waals force between Fe and-Nh_(3),*** the interaction of AA@Fe^(0)with TbP and DD,Van der Waal force plays an important ***@Fe^(0)was synthesized in laboratory and characterized to investigate physicochemical *** Fenton-like degradation of organic solvents,the change of COD in water phase during the degradation process as well as the volume of the organic phase after the reaction were *** results of calculations combined with experiments showed that Ser-modified Fe^(0)performed the best in these amino acids,with 98%removal of organic solvents.A possible catalytic mechanism was proposed in which amino acids acted a linking role between Fe and organic solvents,activating h_(2)O_(2)to generate hydroxyl radicals for the degradation of organic solvents.

关键词： Amino acids Nanoscale zero-valent iron Density functional theory Organic solvents Fenton-like degradation

EXPERIMENTAL AND ThEORETICAL INVESTIGATION OF PSEUDOELASTIC hYSTERESIS IN ShAPE MEMORY ALLOYS

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Acta Metallurgica Sinica(English Letters) 1999年第3期12卷 235-240页

作者： Gong, S.K. xu, h.b. beijing Univ of Aeronautics and Astronautics Beijing China

The pseudoelastic hysteresis loop associated with phase equilibrium and the stress relaxation on the yield line were investigated, and the theoretical description was confirmed by deformation controlled load-deformation measurements on CuZnAl single crystals. It was found that in a loading-unloading process, the states of shape memory alloys run through a hysteresis loop, and the points that trigger the internal yield and recovery inside the pseudoelastic hysteresis loop define a line that traverses the hysteresis loop from the upper left to the lower right corner. This line was interpreted as a line of unstable phase equilibrium according to the thermodynamic arguments, which determines also the tendency for stress relaxation on the yield line section and for a stress growth on the recovery line section.

关键词： Aluminum copper alloys hysteresis Stress relaxation

Distributed generalized Nash equilibrium seeking:event-triggered coding-decoding-based secure communication

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Science China(Information Sciences) 2024年第7期67卷 271-284页

作者： Shaofu YANG Wenying xu Wangli hE Jinde CAO School of Computer Science and Engineering Southeast University School of Mathematics Southeast University Key Laboratory of Advanced Control and Optimization for Chemical Processes East China University of Science and Technology

In this paper, we consider the distributed generalized Nash equilibrium(GNE) seeking problem in strongly monotone games. The transmission among players is implemented through a digital communication network with limited bandwidth. For improving communication efficiency or/and security, an event-triggered coding-decoding-based communication is first proposed, where the data(decision variable) are first mapped to a series of finite-level codewords and, only when an event condition is satisfied, then sent to the neighboring agents. Moreover, a distributed communication-efficient GNE seeking algorithm is constructed accordingly,and the overrelaxation scheme is further taken into consideration. Through primal-dual analysis, the proposed algorithm is proven to converge to a variational GNE with fixed step-sizes by recasting it as an inexact forward-backward iteration. Finally, numerical simulations illustrate the benefit of the proposed algorithms in terms of saving communication resources.

关键词： noncooperative games event-triggered communication coding-decoding quantization